Project Summary The focus of the present SBIR program is to determine the feasibility of a new noninvasive, point-of-care testing device for patients undergoing treatment for substance use disorder. The new device will be capable of monitoring the progress and verifying adherence with patient treatment regimen by detecting the presence (and level) of a compounded adherence marker released in the urine, providing for the first time a device capable of at-site monitoring of treatment adherence for treatment outcome in clinical trials and patient treatment programs. Our program to develop this new point-of-care approach uses surface-enhanced Raman spectroscopy (SERS) for detecting and quantifying the medication adherence tracer, utilizing the Company's unique nanoparticle surface-coating chemistry to detect the adherence biomarker in a patient's urine sample. A significant advantage of our surface-enhanced Raman technique on a properly prepared nanoparticle surface -- relying on the uniqueness of the molecular vibrational signature for differentiation and identification of the adherence biomarkers present in urine -- is that it requires no sample preparation or chemical manipulation to detect the biomarker in the urine sample.